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Combination of Light Emitting Diode at 375 nm and Photo-reactive TiO2 Layer Prepared by Electrostatic Spraying for Sterilization

  • Hwang, Kyu-Seog;Jeon, Young-Sun;Choi, Tae-Il;Hwangbo, Seung
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.1169-1174
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    • 2013
  • The objective of this work was to increase the efficiency of ultraviolet-light emitting diodes at 375 nm for sterilization. Since $TiO_2$ had antibacterial properties, which were attributed to the appearance of hydroxyl radicals and superoxide radical anions on the surface species under ultra violet radiation at about 387 nm, photo-reactive layers such as Ag-doped $TiO_2$ were coated on aluminum substrates by electrostatic spraying. Crystallinity and surface morphology of the coating layer were examined by X-ray diffraction ${\theta}-2{\theta}$ scan and field emission-scanning electron microscope, respectively. In an antibacterial test, we observed above 99% reduction of Escherichia coli populations on 3 or 5 mol% Ag-doped $TiO_2$ layers after irradiation for 2 hrs at 375 nm, while very low inactivation on bare aluminum substrates occurred after irradiation as the same condition.

Nuclear localization of Obox4 is dependent on its homeobox domain

  • Park, Geon Tae;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.40 no.1
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    • pp.1-6
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    • 2013
  • Objective: Oocyte-specific homeobox 4 (Obox4) is preferentially expressed in oocytes and plays an important role in the completion of meiosis of oocytes. However, the Obox4 expression pattern has not been reported yet. In this study, we investigated the subcellular localization of Obox4 using a green fluorescent protein (GFP) fusion expression system. Methods: Three regions of Obox4 were divided and fused to the GFP expression vector. The partly deleted homeodomain (HD) regions of Obox4 were also fused to the GFP expression vector. The recombinant vectors were transfected into HEK-293T cells plated onto coated glass coverslips. The transfected cells were stained with 4',6-diamidino-2-phenylindol and photographed using a fluorescence microscope. Results: Mutants containing the HD region as well as full-length Obox4 were clearly localized to the nucleus. In contrast, the other mutants of either the N-terminal or C-terminal region without HD had impaired nuclear localization. We also found that the N-terminal and C-terminal of the Obox HD contributed to nuclear localization and the entire HD was necessary for nuclear localization of Obox4. Conclusion: Based on the results of the present study, we demonstrated that the intact HD region of Obox4 is responsible for the nuclear localization of Obox4 protein in cells.

Effects of Monoclonal Antibodies against Human Stathmin Combined with Paclitaxel on Proliferation of the QG-56 Human Lung Carcinoma Cell Line

  • Yuan, Shao-Fei;Chen, Wen-Jun;Zhu, Lin-Jia;Zheng, Wei-E.;Chen, Hua;Xiong, Jian-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2967-2971
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    • 2012
  • Objective: To explore whether monoclonal antibodies against stathmin and the chemotherapuetic agent paclitaxel have synergenic effects in inhibiting growth and inducing apoptosis in human QG-56 cells. Methods: QG-56 cells were treated with monoclonal antibodies against stathmin or paclitaxel alone or in combination, with untreated cells used as controls. After 24, 48, 72 and 96 hours the cell growth condition was observed under an inverted microscope and inhibition was studied by MTT assay; apoptosis was analyzed by flow cytometry. Results: The populations decreased and cell shape and size changed after the various treatments. Monoclonal antibodies against stathmin and paclitaxel used alone or incombination inhibited the proliferation of QG-56 cells, especially in combination with synergism (P<0.05). Combined treatment also resulted in a significantly higher apoptosis rate than in the other groups (P<0.05). Conclusions: Monoclonal antibodies against stathmin and paclitaxel used alone or in combination can inhibit proliferation of QG-56 cells and induce apoptosis when applied together. The observed synergistic effects may have important implications for clinical application.

The Effects of electroacupuncture stimuli to the Doublecortin and PSA-NCAM positive cells in the Dentate Gyrus of spontaneously hypertensive rats (전침(電鍼)자극이 SHR 흰쥐의 Dentate Gyrus에서의 Doublecortin과 PSA-NCAM 양성 신경세포에 미치는 영향)

  • Woo, Hyun-su;Lee, Jae-dong;Kim, Chang-hwan
    • Journal of Acupuncture Research
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    • v.20 no.2
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    • pp.123-134
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    • 2003
  • Objective : This experimental in vitro study investigates the effects of electro acupuncture stimuli to the DCX and PSA-NCAM positive cells in the dentate gyrus of spontaneously hypertensive rats. Methods : We used immunohistochemical methods to observe the change of neuron cells, and then counts the immunoactive cells under the $100{\times}$ visual field optical microscope. Results : 1. The counts of DCX-positive cells in the dentate gyrus significantly increased in the 2Hz group versus control group. Otherwise 100Hz group did not have a significant differance. 2. The counts of PSA-NCAM-positive cells in the dentate gyrus rather decreased in the both 2Hz group and 100Hz group versus control group. Conclusions : We find out the electro acupuncture stimuli have some effects upon cerebral neuron cell in the dentate gyrus spontaneously hypertensive rats.

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Evaluation of different enamel conditioning techniques for orthodontic bonding

  • Turkoz, Cagri;Ulusoy, Cagri
    • The korean journal of orthodontics
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    • v.42 no.1
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    • pp.32-38
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    • 2012
  • Objective: The aim of this study was to compare the effects of different enamel conditioning techniques for bracket bonding. Methods: Ninety-one human premolars were randomly divided in six groups of 15 specimens each. The enamel surfaces of the teeth were etched with 35% orthophosphoric acid in Group 1, with a self-etching primer in Group 2, sandblasted in Group 3, sandblasted and etched with 35% orthophosphoric acid in Group 4, conditioned by Er:YAG laser in Group 5 and conditioned by Er:YAG laser and etched with 35% phosphoric acid gel respectively in Group 6. After enamel conditioning procedures, brackets were bonded and shear bonding test was performed. After debonding, adhesive remnant index scores were calculated for all groups. One tooth from each group were inspected by scanning electron microscope for evaluating the enamel surface characteristics. Results: The laser and acid etched group showed the highest mean shear bond strength (SBS) value ($13.61{\pm}1.14$ MPa) while sandblasted group yielded the lowest value ($3.12{\pm}0.61$ MPa). Conclusions: Although the SBS values were higher, the teeth in laser conditioned groups were highly damaged. Therefore, acid etching and self-etching techniques were found to be safer for orthodontic bracket bonding. Sandblasting method was found to generate inadequate bonding strength.

A Study of Porcelain Bond Strength to Cast Ti Alloy with respect to Change of Surface Characteristic (표면 변화에 따른 주조용 티타늄 합금과 도재와의 결합강도 변화에 관한 연구)

  • Chung, In-Sung;Choi, Sung-Min
    • Journal of Technologic Dentistry
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    • v.30 no.1
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    • pp.65-71
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    • 2008
  • The use of titanium in the field of dentistry has increased, due to their excellent biocompatibility, appropriate mechanical properties, corrosion-resistance and low price. However, many difficulties with the use of titanium for metal-ceramic crowns remain to be solved. The objective of this study was to evaluate the influence of surface modifications on the bonding characteristics of specific titanium porcelain bonded to cast titanium. The surfaces of Titanium were prepared with 4 test groups, i) sandblasted with particles of different size, ii) sandblasted after treated oxidization and oxidized after sandblast. We observed the bond strength and node aspect of titanium and ceramic, and respect to the methods of modifying surface of titanium by the test of mean roughness of surface, Scanning Electron Microscope, and 3-point flexural bend test. The results show that, 1. The specimens, which treated oxidization after process of sandblast with particles of 50um size, were the better for the bond strength in comparison with other specimen. 2. The specimen with process of sandblasting after oxidization treatment were the better for stability of the bond strength. 3. The wettability of titanium surface affect the bond strength.

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Folate-Targeted Nanostructured Lipid Carriers (NLCs) Enhance (Letrozol) Efficacy in MCF-7 Breast Cancer Cells

  • Sabzichi, Mehdi;Mohammadian, Jamal;Khosroushahi, Ahmad Yari;Bazzaz, Roya;Hamishehkar, Hamed
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5185-5188
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    • 2016
  • Objective: Targeted-drug-delivery based lipid nanoparticles has emerged as a new and effective approach in cancer chemotherapy. Here, we investigated the ability of folate-modified nanostructured lipid carriers (NLCs) to enhance letrozol (LTZ) efficacy in MCF-7 breast cancer cells. Methods: New formulations were evaluated regarding to particle size and scanning electron microscope (SEM) features. Anti-proliferative effects of LTZ loaded nanoparticles were examined by MTT assay. To understand molecular mechanisms of apoptosis and cell cycle progression, flow cytometric assays were applied. Results: Optimum size of nanoparticles was obtained in mean average of $98{\pm}7nm$ with a poly dispersity index (PDI) of 0.165. The IC50 value was achieved for LTZ was $2.2{\pm}0.2{\mu}M$. Folate-NLC-LTZ increased the percentage of apoptotic cells from 24.6% to 42.2% compared LTZ alone (p<0.05). Furthermore, LTZ loaded folate targeted NLCs caused marked accumulation of cells in the subG1 phase. Conclusion: Taken together, our results concluded that folate targeted LTZ can be considered as potential delivery system which may overcome limitations of clinical application of LTZ and improve drug efficacy in tumor tissue.

Effects of Oxygen Plasma Treatment on the Wettability of Polypropylene Fabrics

  • Kwon, Young Ah
    • Fashion & Textile Research Journal
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    • v.16 no.3
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    • pp.456-461
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    • 2014
  • The objective of this study is to give PP(polypropylene) fabric a good affinity for water. Oxygen plasma was treated to PP fabrics in a commercial glow discharge reactor with different RF power, discharge pressure, and reaction time. The PP fiber surfaces were characterized by the measurement of contact angle and ESCA. A JEOL scanning electron microscope was used to observe the surface morphology of fibers. The spontaneous water uptake amount of PP fabrics was determined by the demand wettability test. To determine the effect of aging on the surface properties of $O_2$ plasma treated PP, all the above measurements of the samples were carried out after 1, 7, 30, 60, and 150 days. The results are as follows. The PP fiber surfaces treated by $O_2$ plasma treatment have a chemical composition that consisted of various oxygen containing polar groups. Consequently, the contact angles of the treated PP fibers decreased, which improved the water uptake rate of PP fabrics. Surface roughness of the treated PP affected the fabric wettabiity as well. Wettability of the treated PP decreased and leveled off with aging. The $O_2$ plasma treatment is a simple and effective method to increase the water uptake rate of PP fabrics.

Ultrastructures of Colletotrichum orbiculare in Cucumber Leaves Expressing Systemic Acquired Resistance Mediated by Chlorella fusca

  • Kim, Su Jeung;Ko, Eun Ju;Hong, Jeum Kyu;Jeun, Yong Chull
    • The Plant Pathology Journal
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    • v.34 no.2
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    • pp.113-120
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    • 2018
  • Chlorella, one single-cell green algae organism that lives autotrophically by photosynthesis, can directly suppress some plant diseases. The objective of this study was to determine whether pre-spraying with Chlorella fusca suspension could induce systemic acquired resistance (SAR) in cucumber plants against anthracnose caused by Colletotrichum orbiculare. In order to illustrate SAR induced by algae, infection structures in host cells were observed under a transmission electron microscope (TEM). Cytological changes as defense responses of host mesophyll cells such as accumulation of vesicles, formation of sheath around penetration hyphae, and thickness of cell wells adjoining with intracellular hyphae were demonstrated in cucumber leaves. Similar defense responses were also found in the plant pre-treated with DL-3-aminobutyric acid, another SAR priming agent. Images showed that defense response of host cells was scarcely observed in untreated leaf tissues. These cytological observations suggest that C. fusca could induce SAR against anthracnose in cucumber plants by activating defense responses of host cells.

Experimental study on feasibility test for removing particles in air scouring membrane backwash water with metal membrane (금속막을 이용한 저압 막 공기병용 역세척수 처리 타당성 연구)

  • Park, No-Suk;Yoon, Sukmin;Moon, Yong-Taik;Lee, Sun-Ju;Park, Sunghyuk
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.2
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    • pp.251-259
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    • 2015
  • The main objective of this research is to study feasibility for applying metal membrane to remove particles from air scouring membrane backwash water. Also, the research was conducted to investigate the influence of polyamine coagulation on floc growth in membrane backwash water as pretreatment for removal particles. From the results of experiments for evaluating the influence of polyamine coagulation on floc growth, it was investigated that particles in the rage of $2{\sim}50{\mu}m$ grew up to $30{\sim}5,000{\mu}m$. In addition, all six metal membranes showed lower removal efficiency, which was 0.87~13.89%, in the case of no polyamine coagulant. On the other hand, in the case of injecting polyamine coagulant, those did extremely high efficiency in 56~92%. From the SEM(Scanning Electron Microscope) images of filtered wiremesh and metal foam membrane, sieve effects were predominant for liquid solid separation in wiremesh and adsorption and diffusion capture effects were predominant in metal foam membrane.